import { DirectiveBinding } from "vue";
import { nextTick } from "vue";

export default {
  mounted(el: HTMLElement, binding: DirectiveBinding, vnode: any) {
    nextTick(() => {
      const dialogHeaderEl = el.querySelector(".el-dialog__header") as HTMLElement;
      const dragDom = el.querySelector(".el-dialog") as HTMLElement;
      console.log(dialogHeaderEl,dragDom);
      
      dialogHeaderEl.style.cursor = "move";
      dragDom.style.top = "18%";
      dragDom.style.left = "1%";

      // 弹框可拉伸最小宽高
      let minWidth = 0;
      let minHeight = 0;

      setTimeout(() => {
        minWidth = dragDom.clientWidth;
        minHeight = dragDom.clientHeight;
      }, 300);

      // 获取原有属性，兼容 IE 和现代浏览器
      const getStyle = (dom: HTMLElement, attr: string): string => {
        if (window.getComputedStyle) {
          return window.getComputedStyle(dom, null).getPropertyValue(attr);
        } else {
          return "";
        }
      };

      dialogHeaderEl.onmousedown = (e: MouseEvent) => {
        e.preventDefault();
        // 鼠标按下，计算当前元素距离可视区的距离
        const disX = e.clientX - dialogHeaderEl.offsetLeft;
        const disY = e.clientY - dialogHeaderEl.offsetTop;

        const dragDomWidth = dragDom.offsetWidth;
        const dragDomHeight = dragDom.offsetHeight;

        const screenWidth = document.body.clientWidth;
        const screenHeight = document.body.clientHeight;

        const minDragDomLeft = dragDom.offsetLeft;
        const maxDragDomLeft = screenWidth - dragDom.offsetLeft - dragDomWidth;

        const minDragDomTop = dragDom.offsetTop;
        const maxDragDomTop = screenHeight - dragDom.offsetTop - dragDomHeight;

        // 获取到的值带px 正则匹配替换
        let styL: string | number = getStyle(dragDom, "left");
        let styT: string | number = getStyle(dragDom, "top");

        if (typeof styL === "string" && styL.includes("%")) {
          styL = (parseFloat(styL) / 100) * document.body.clientWidth;
          styT = (parseFloat(styT) / 100) * document.body.clientHeight;
        } else {
          styL = parseFloat(styL as string);
          styT = parseFloat(styT as string);
        }

        document.onmousemove = function (e: MouseEvent) {
          // 通过事件委托，计算移动的距离
          let left = e.clientX - disX;
          let top = e.clientY - disY;

          // 边界处理
          if (-left > minDragDomLeft) {
            left = -minDragDomLeft;
          } else if (left > maxDragDomLeft) {
            left = maxDragDomLeft;
          }

          if (-top > minDragDomTop) {
            top = -minDragDomTop;
          } else if (top > maxDragDomTop) {
            top = maxDragDomTop;
          }

          // 移动当前元素
          dragDom.style.left = `${left + styL}px`;
          dragDom.style.top = `${top + styT}px`;

          // emit onDrag event
          vnode.component?.emit("dragDialog");
        };

        document.onmouseup = function () {
          document.onmousemove = null;
          document.onmouseup = null;
        };
      };

      // 双击弹窗顶部 最大化 / 最小化
      dialogHeaderEl.ondblclick = () => {
        if (vnode.context && typeof vnode.context.setFullScreen === "function") {
          vnode.context.setFullScreen();
        } else {
          console.error("setFullScreen 方法未定义或 vnode.context 不存在");
        }
      };

      // 缩放窗口
      const resizeEl = document.createElement("div");
      dragDom.appendChild(resizeEl);
      // 在弹窗右下角加上一个10-10px的控制块
      resizeEl.style.cursor = "nwse-resize";
      resizeEl.style.position = "absolute";
      resizeEl.style.height = "10px";
      resizeEl.style.width = "10px";
      resizeEl.style.right = "0px";
      resizeEl.style.bottom = "0px";

      // 鼠标拉伸弹窗
      resizeEl.onmousedown = (e: MouseEvent) => {
        // 鼠标按下，计算当前元素距离可视区的距离
        const disX = e.clientX - resizeEl.offsetLeft;
        const disY = e.clientY - resizeEl.offsetTop;

        document.onmousemove = function (e: MouseEvent) {
          e.preventDefault(); // 移动时禁用默认事件
          // 通过事件委托，计算移动的距离
          const x = e.clientX - disX + 10;
          const y = e.clientY - disY + 10;
          // 比较是否小于最小宽高
          dragDom.style.width = x > minWidth ? `${x}px` : `${minWidth}px`;
          dragDom.style.height = y > minHeight ? `${y}px` : `${minHeight}px`;
        };

        document.onmouseup = function () {
          document.onmousemove = null;
          document.onmouseup = null;
        };
      };
    });
  },
  beforeUnmount(el: HTMLElement) {
    const dialogHeaderEl = el.querySelector(".el-dialog__header") as HTMLElement;
    const resizeEl = el.querySelector(".el-dialog > div:last-child") as HTMLElement;

    if (dialogHeaderEl) {
      dialogHeaderEl.onmousedown = null;
      dialogHeaderEl.ondblclick = null;
    }

    if (resizeEl) {
      resizeEl.onmousedown = null;
      resizeEl.remove();
    }
  }
};